Dump valves are fitted to the engines of turbo charged cars and sit between the turbo outlet and the throttle body. These are known for the "tissh" sound when you change gear.
Found already fitted in cars such as a subaru.

Assimilation of a lot of information and forgetting it as soon as the necessity for learning it is over. Originates from filling the fuel tanks of an aircraft, taking off, and then immediately dumping the fuel prior to landing in order to (1) train using the dump valve, (2) use up the squadron's allocation of fuel so that the allocation will not be reduced the next year (especially popular at the end of the fiscal year), and (3) ensure a safe landing (most aircraft cannot safely land full of fuel).

The asshole on a woman. The valve that opens and closes when a woman takes a dump.

The act of defecating into a fellow-human's mouth such as to choke him with the size of the defecant. C.f. "shit eater."

An accronym meaning, "RIP ASS MULTIPLICATOR". A device derived from taking out the main valve from a trumpet and ripping ass into the bell. The original inventors of this device are scientist/musicians Travis Dosser and Patrick Opp. The R.A.M amplifies the rip ass sound, and smell by adding the component of spit from the trumpet.

Tuning legend. Also see tork.

peaked baseball cap possibly fake burberry
as much jewellery as is able to carry on his skinny under nourished body due to parents sponging off the government spending food money on 80 sovereign a day.
jewellery from the mr t reject collection
consistently stoned or angry or both
white shoes preferably prism white with metallic nike tick on the side
tracksuit bottoms tucked into white socks
nike addidas lonsdale tshirts for example, mainly fake
always looking for a fight
little or no education
no jobs
own a stolen nova or corsa with neons a spoiler and a dump valve(like to write turbo on the back although there isnt one)
live off benefits ther entire live
and steal hubcaps and start on anyone in a smaller group than them